Exploration of the effect of simultaneous removal of EDCs in the treatment process of different types of wastewater.

The SPE-HPLC-MS/MS method was used to investigate the concentration distribution of nine types of estrogens in 18 locations of pollution source along the Jiuzhou River belonging to river systems in Guangdong province and Guangxi Zhuang autonomous region in China, and the estrogenic activity and potential ecological risks were evaluated by calculating the estradiol equivalency (EEQ). The results showed that the calculated estradiol equivalents (cEEQs) of wastewater treatment plants from 17 locations were all higher than 1 ng/L. To further study the removal effect of the treatment process on the estrogens, the pig breeding wastewater from P4 and the municipal wastewater from P13, as well as the black-odorous water, were sampled and surveyed during the entire process. It turned out that estrogens were effectively removed after nitrification activated sludge treatment. Meanwhile, there was a positive correlation between the removal of NH3-N, total nitrogen (TN) and total phosphorus (TP) and the removal of endocrine disrupting chemicals (EDCs). It is shown in the study the secondary treatment process has achieved a significant effect on the removal of estrogen in both the wet and dry periods and that there has been a positive correlation between the activities of total phosphorus compounds, nitrogen-based compounds and the removal of EDCs.

A stable Fe/Co bimetallic modified biochar for ofloxacin removal from water: adsorption behavior and mechanisms.

In this study, Fe-Co-modified biochar (FMBC) loaded with iron (Fe) and cobalt (Co) bimetals after NaOH activation was prepared by pyrolysis using forestry waste cedar bark as a raw material to study its properties and the adsorption of ofloxacin (OFX). The surface structure and chemical properties were analyzed by BET, SEM-EDS, XRD, XPS, and FTIR characterization, and the results showed that the FMBC possessed a larger specific surface area and abundant surface functional groups. FMBC conformed to pseudo-second-order kinetic and Langmuir isotherm models, indicating that the OFX adsorption process on FMBC was a monolayer adsorption process and controlled by chemisorption. The saturation adsorption capacity of FMBC was 10 times higher than that of cedar bark biochar (BC). In addition, the effects of initial pH and coexisting ions on the adsorption process were investigated, and FMBC showed good adsorption, with the best adsorption capacity at pH = 7. Multiple adsorption mechanisms, including physical and chemical interactions, were involved in the adsorption of OFX by FMBC. TG, metal leaching, different water sources, and VSM tests showed that FMBC had good stability and was easily separated from water. Finally, the reusability performance of FMBC was investigated by various methods, and after five cycles it could still reach 75.78-89.31% of the adsorption capacity before recycling. Therefore, the FMBC synthesized in this study is a promising new adsorbent.

Occurrence and removal of 25 antibiotics during sewage treatment processes and potential risk analysis.

The occurrence and removal of 25 antibiotics, including ten quinolones (QNs), four macrolides (MLs), four tetracyclines (TCs) and seven sulfonamides (SNs), were analysed at two sewage treatment plants (STPs) with different treatment units in Guangxi Province, China. The results showed that 14 and 16 antibiotics were detected in the influent of the two STPs, with concentrations ranging from 13.7-4265.2 ng/L and 14.5-10761.7 ng/L, respectively. Among the antibiotics, TCs were the main type in the study area, accounting for more than 79% of the total concentration of all antibiotics. The antibiotic removal efficiencies of the different process units ranged from -56.73% to 100.0%. It was found that the SN removal efficiency of the multistage composite mobile bed membrane bioreactor (MBBR) process was better than that of the continuous-flow Intermission biological reactor (IBR) process, while the IBR process was better than the MBBR process in terms of removing TCs and MLs; however, there was no obvious difference in the QN removal efficiencies of these two processes. Redundancy analysis (RDA) showed a strong correlation between antibiotic concentration and chemical oxygen demand (COD). Risk assessments indicated that algae, followed by invertebrates and fish, were the most sensitive aquatic organisms to the detected antibiotics.

Characterization of Edible Fungus Substrate Modified Biochar and Its Adsorption Capacity for Ciprofloxacin Hydrochloride.

In this study, silver-ytterbium-modified biochar (MBC) was prepared to adsorb ciprofloxacin hydrochloride. It was compared with biochar (BC) and alkali-modified biochar (NBC). The results show that the MBC had more functional groups and a larger specific surface area than the BC and NBC. The saturated adsorption capacity of the MBC (312.500 mg g-1) was 3 and 19 times higher than that of the NBC and BC, respectively. The adsorption data were consistent with the pseudo-second-order kinetics model and the Langmuir isotherm model. In addition, the mechanism of CIP adsorption onto NBC and MBC may be dominated by π-π electron donor-accepter interactions. C-O, C=O and -NH2 play important roles in adsorption, and Ag-O and Yb-O groups participate in the adsorption of CIP onto MBC.

[Immobilization impact of different fixatives on heavy metals contaminated soil].

Four kinds of amendments including humus, ammonium sulfate, lime, superphosphate and their complex combination were added to rapid immobilize the heavy metals in contaminated soils. The best material was chosen according to the heavy metals' immobilization efficiency and the Capacity Values of the fixative in stabilizing soil heavy metals. The redistributions of heavy metals were determined by the European Communities Bureau of Referent(BCR) fraction distribution experiment before and after treatment. The results were as follows: (1) In the single material treatment, lime worked best with the dosage of 2% compared to the control group. In the compound amendment treatments, 2% humus combined with 2% lime worked best, and the immobilization efficiency of Pb, Cu, Cd, Zn reached 98.49%, 99.40%, 95.86%, 99.21%, respectively. (2) The order of Capacity Values was lime > humus + lime > ammonium sulfate + lime > superphosphate > ammonium sulfate + superphosphate > humus + superphosphate > humus > superphosphate. (3) BCR sequential extraction procedure results indicated that 2% humus combined with 2% lime treatment were very effective in immobilizing heavy metals, better than 2% lime treatment alone. Besides, Cd was activated firstly by 2% humus treatment then it could be easily changed into the organic fraction and residual fraction after the subsequent addition of 2% lime.